Valve grinding machinery



\ 'VALVE GRINDING MACHINERY Filed Nov. 2l, 1953 :Snventor ,v

Both

(Ittomegs Patented Apr. 30, 1935 UNITED i sTATss ingang gran ori-ica Claims.

This invention relates to improvements in grinding machinery, and more particularly vto improved machinery adapted for use in the grinding of headed articles such as automobile valves 5 of the mushroom type.

One of the main objects of the invention is to provide a grinder in which the conical valve face is held in non-slipping relation to the face of the as in the usual centerless grinder.

A further object of the invention is to provide a structure in which the two wheels of the grinder engage the work from opposite sides, thus holding the work in balanced relation and counteracting any tendency of the work to chatter during the grinding operation.

Another object of the invention is to provide a machine in which the smaller diameter of the Work is always in contact with the smaller diameter of the regulating wheel, thus promoting proper engagement between the wheel and the work and preventing the formation of irregular surfaces on the work.

Still a further object of the invention is to provide a machine in which cup-shaped grinding wheels only are employed, and in which the wheel surfaces engaging the work are of small width so as to cut down the amount of work required for truing operations performed on the wheels.

Other objects and advantages of the invention will be understood from the following specification when read in conjunction with the accompanying drawing, in which the single figure is a plan view of one form of machine embodying this invention.

Referring to the drawing, the reference character 4 designates generally the base of the ma-4 chine upon which the working parts are carried. Mounted on this base i are two heads 5 and 6, each carrying a rotating wheel. Rotatably The wheel 'I is held on the axle in any suitable manner, as for example by a nut i l. This wheel and axle are adjustable by means of a hand wheel 724i.

Mounted on the head E2 and arranged for rotative adjustment, and likewise for axial adjustment by means of hand wheel i2, is a rotatable grinding wheel i3 of cup formation and having a narrow grinding surface it adapted to contact with the Work. In practice, the wheel I3 will be driven by a suitable mechanism of conventional character and at a speed considerably higher than that imparted to the regulating wheel l. Likewise, the diameter of Wheel i3 is materially greater than that of the wheel l, this being the usual practicein the centerless grinder art.

Mounted on the base 4 is a valve-carrying holder l5. This holder is provided at its forward end with a V-shaped receiving notch iii adapted to receive the small end of a valve stem il and having a groove at its rear end i9 to receive the shank of the stem adjacent the head. In practice, means are provided for clamping the stem to the holder.

The holder i5 may be mounted on a suitable slide 2i and arranged to reciprocate to and from wheel-engaging position under the inuenceof either manual or automatic adjusting means.

It will be noted that the arrangement of the parts is such as to permit the holder i5 to be passed through the grinding throat between Wheels l and i3 without engaging either of these wheels. Consequently, the holder may be entirely retracted from the grinding throat and made accessible for mounting and dismounting of the work.

The head 22 of the valve is to be ground with a conical surface 23 in the usual manner, the valve having been roughly formed previous to the grinding operation. Accordingly, when the valve is mounted in the holder l5 and moved to the position shown in the drawing, the face 23 of the valve engages both the surface 8 of the regulating wheel 'i and the grinding surface i4 of grind- The action of the regulating wheel will be such as to rotate the valve and to cause an abrading action at the point of contact of the valve surface 23 and the surface lli of grinding wheel I3. The grinding operation is continued until the face 23 is smooth and of the desired characteristie, whereupon the valve may bey withdrawn by withdrawing the slide 2l from the grinding throat.

The relation of the bevel surface 8 of the regulating wheel and the face 23 of the valve is such that the smaller diameter of the face 23 contacts the smaller diameter of the face 8. Consequently, tendency to slippage between the Work and the regulating wheel is reduced to a minimum, and the work may be ground quickly and accurately.

In addition to this, the width of the face 8 and of the face I3 is very small, so that when a truing operation is necessary on either or both of these surfaces, it can be carried out quickly and expeditiously. On the other hand, were these grinding and regulating wheels of either cylindrical or cone shape, an abrading surface of substantial extent would have to be trued each time a truing operation became necessary.

What is claimed is:

1. A machine for grinding conical valves, comprising two cup wheels having their axes disposed in non-parallel relation and mounted to provide clearance in excess of the thickness of the stem of a valve to be ground; and a holder for supporting a Valve stem and movable between said wheels to 'bring the valve face to be ground into contact with the narrow faces of said cups.

2. A machine for grinding valves, comprising a cupped regulating wheel; a cupped grinding wheel; and means movable between said wheels for supporting the stem of a valve to be ground, and for bringing the valve face into contact with the narrow faces of both of said cups.

3. A machine for grinding valves, comprising a movable holder constructed and arranged to support the stem of a valve to be ground; a cup-shaped regulating wheel having the narrow lateral face of the cup beveled for contact with the valve surface; and a cup-shaped grinding wheel mounted on the other side of said holder Y mushroom valves,

remote from said regulating wheel, said wheel being so spaced with reference to the rst Wheel as to permit said holder to pass between said wheels and bring the valve into contact with the beveled face of the regulating wheel and the narrow face of the grinding wheel.

4. A machine for grinding the conical faces of comprising a cupped grinding wheel, having a narrow work-engaging surface; a cupped regulating wheel having anarrow beveled face; a holder adaptedr to support the stem of a valve to be ground and arranged to pass between said wheels, and to bring the valve face into contact with the narrow faces of both said wheels; means for driving said wheels; and means for adjusting both oi said wheels relative to the holder,

5. A machin for grinding the conical faces of mushroom valves, comprising a cupped regulating wheel having a narrow beveled work-engaging face; a cupped grinding wheel having a narrow lateral work-engaging face, the axis of said grinding wheel being in non-parallel relation to' the axis of the regulating wheel so that said lateral face and said beveled face form a tapered grinding throat; and a holder adapted to support the stem of a Valve to be ground and arranged to pass between 'said wheels to head into said grinding throat.

CHARLES I. LO'IT.

bring the valve alot 

